1. Field of Invention
The present invention relates to double-sided liquid crystal display devices, and particularly, to a double-sided liquid crystal display device which is provided with liquid crystal display panels and a double-sided light source assembly that emits light from two sides thereof to function as a backlight for the display panels. In such a device, each liquid crystal display panel is disposed adjacent to any position at each side of the light source assembly. An image display operation is performed by switching between the display panels.
2. Description of Related Art
Double-sided liquid crystal display devices have been used in mobile information terminals, such as mobile phones and PDAs (Personal Digital Assistants) that are provided with foldable covers. On the inner and outer surfaces of the cover of such an information terminal, two liquid crystal display units are disposed in a back-to-back manner to form a double-sided liquid crystal display device. The two liquid crystal display units of related art devices are each provided with a liquid crystal display panel combined with a backlight, and the two units are disposed in a back-to-back manner.
Furthermore, in one related art approach to reduce the thickness of the backlights for the liquid crystal display panels disposed on the two sides of, for example, the cover, light-guiding plates of the backlights for the two liquid crystal display panels are wedge-shaped in cross section. Thus, these light-guiding plates are disposed adjacent to each other such that the two inclined planes of the plates face each other. Moreover, these light-guiding plates are each provided with a light source to emit light, which is disposed adjacent to a side of each plate. Consequently, the thickness of the backlight is reduced. See Japanese Unexamined Patent Application Publication No. 2002-244133.
As another approach to reduce the thickness of the backlights for the liquid crystal display panels disposed on the two sides of, for example, the cover, a related art device uses a common light-guiding plate which can emit light from both sides of the plate. See Japanese Unexamined Patent Application Publication No. 2001-67049.